The Supreme Court will today give a ruling in a landmark legal battle between education chiefs and a father who took his daughter on holiday in term-time without her headteacher's permission.

Their findings could have significant implications for families across England.

The judges are ruling on an appeal by Isle of Wight Council in a case involving Jon Platt, who took his daughter on a seven-day family trip to Disney World in Florida in April 2015.

The council prosecuted Mr Platt after he refused to pay a £120 penalty. Local magistrates found there was no case to answer and the council took its case to the High Court in London, where two judges upheld the decision.

Speaking ahead of the judgment, Mr Platt said that if the Supreme Court rules in favour of the argument put forward by education bosses, it "means that regularly attending school means attending every day, whenever the school demands it, 100 per cent attendance".

"That will criminalise 6-7 million parents," he said. "Being one minute late will be a criminal offence."

Here is the background and the key issues involved.

What is this case about?

In April 2015, businessman Jon Platt took his daughter out of school without permission for a seven-day trip to Disney World, Florida. He was fined for doing so and later prosecuted by the Isle of Wight council for refusing to pay the £120 penalty.

But local magistrates found there was no case to answer, and the council took its case to the High Court in London.

At the High Court hearing last year, Lord Justice Lloyd Jones and Mrs Justice Thirlwall dismissed the council's renewed challenge and said the magistrates were entitled to take into account the ''wider picture'' of the child's attendance record outside of the dates she was absent for the holiday.

The two judges upheld the magistrates' decision and declared Mr Platt was not acting unlawfully because his daughter had a good overall attendance record of over 90 per cent.

The case did not finish here, the Isle of Wight council appealed to the Supreme Court, the highest court in the land, with the backing of the government.

It is this court's ruling which will be made today.

Why is this case so important?
The crux of the matter is that five Supreme Court judges are being asked to consider whether or not Mr Platt committed an offence by failing to ensure his daughter ''attended school regularly'', as required by section 444(1) of the 1996 Education Act.

A key High Court finding was that the magistrates who originally heard the case were legally entitled to take into account the daughter's overall attendance record and not just her lack of ''regular attendance'' during the Florida holiday period.

At a Supreme Court hearing in January, the Isle of Wight council argued a child's unauthorised absence from school ''for even a single day, or even half a day'' can amount to a criminal offence.

A QC for Mr Platt, described the submission as a new and radical interpretation of the law which was absurd and would ''criminalise parents on an unprecedented scale''.

The action is being closely watched by parents across the country.

The High Court ruling led to a surge in term-time holiday bookings, and if judges today rule in favour of Mr Platt, this could continue. Parents with children that usually have a high attendance rate could decide it is worth taking them out of lessons and taking advantage of cheaper holiday prices.

If the Supreme Court decides in favour of education bosses, it would mean that schools and local councils could be even tougher on families whose children miss any school without permission.

What are the current rules?
In the autumn of 2013, there was a major crackdown on absence, including term-time holidays.

New rules were brought in, which said headteachers could only grant leave in "exceptional circumstances". Previously, school leaders were able to approve leave of up to 10 days for "special circumstances".

Fines for unauthorised absence were also increased in 2013, with parents now incurring a penalty of £60, rising to £120 if it is not paid within 21 days. anyone who fails to pay within 28 days can face prosecution.

Ministers have argued that children must be in school every day, and that every extra day of school a child misses can affect their GCSE results.

How many children are currently missing school for holidays?
Figures published by the Department for Education last month showed that around a million schoolchildren missed lessons last year after taking family trips during term time.

About one in six pupils in England took at least a half day off for a trip in the 2015/16 academic year with the vast majority doing so without getting permission from the headteacher.

Overall, there were 801,980 pupils in England's state primary, secondary and special schools (11.9 per cent) with one or more sessions (half days) of absence due to unauthorised family holidays, and 223,080 students (3.3 per cent) with at least one missed session due to agreed family breaks.

There are no overall figures on the numbers of parents handed fines for taking children out of school, but figures previously obtained by the Press Association showed that in the 2014/15 academic year, at least 50,414 penalty notices were issued due to children being taken out of lessons for trips.

This was up 25 per cent on the year before, when at least 40,218 penalties were given out, and up 173 per cent from the 18,484 fines handed out by local authorities in 2012/13. These figures cover 71 councils that provided data for all three years.